Google Groups no longer supports new Usenet posts or subscriptions. Historical content remains viewable.
Dismiss

Circular number puzzle

988 views
Skip to first unread message

SH...@slacvm.slac.stanford.edu

unread,
Mar 30, 1992, 4:24:33 PM3/30/92
to
Here's a "Circular" number puzzle for you all.....

ABCDEF * 2 = CDEFAB
ABCDEF * 3 = BCDEFA
ABCDEF * 4 = EFABCD
ABCDEF * 5 = FABCDE
ABCDEF * 6 = DEFABC

Every "A" is the same number, as is every other letter.
No two letters are the same number. No zeros.
It is possible. Good luck.

Rich Wenner

unread,
Mar 30, 1992, 5:41:06 PM3/30/92
to

Not only possible, but piece of cake! But just in case, here's a

SPOILER ALERT !!!

ABCDEF = 142857, which is the digit pattern that repeats in the fraction
1/7.

For grins, note that Shere had to quit giving clues after

ABCDEF * 6 = DEFABC, because
ABCDEF * 7 = 999999
--
Rich Wenner --(o)--(o)-- I really hate this damn machine.
EDS/TSD/DSD/FSD/CSDPS ( /\ ) I wish that they would sell it.
mmmm It never does quite what I mean,
#include <stddisclaimer.h> \____/ But only what I tell it.

MYU...@slacvm.slac.stanford.edu

unread,
Mar 30, 1992, 6:06:24 PM3/30/92
to
Path: slacvm!shere
Organization: Stanford Linear Accelerator Center
Date: Monday, 30 Mar 1992 13:24:33 PST
From: <SH...@SLACVM.SLAC.STANFORD.EDU>
Message-ID: <92090.13...@SLACVM.SLAC.STANFORD.EDU>
Newsgroups: rec.puzzles
Subject: Circular number puzzle

> "Circular" number puzzle for you all.....
>
> ABCDEF * 2 = CDEFAB
> ABCDEF * 3 = BCDEFA
> ABCDEF * 4 = EFABCD
> ABCDEF * 5 = FABCDE
> ABCDEF * 6 = DEFABC

Spoiler:


ABCDEF=142857

Hong Liang Xie

unread,
Mar 30, 1992, 6:30:23 PM3/30/92
to
>Here's a "Circular" number puzzle for you all.....
>
> ABCDEF * 2 = CDEFAB
> ABCDEF * 3 = BCDEFA
> ABCDEF * 4 = EFABCD
> ABCDEF * 5 = FABCDE
> ABCDEF * 6 = DEFABC
>

(SPOILER)

EASY.

142857 * 2 = 285714
142857 * 3 = 428571
142857 * 4 = 571428
142857 * 5 = 714285
142857 * 6 = 857142

Just observe that A = 1 from the last equation.
Then F = 7 by the second equation, as 7 * 3 = 1 (mod 100).
Now it follows that B = 4, D = 8, E = 5, C = 2.


------------------
-Hong, CIS Dept, U of Penn


Ethan Rutter

unread,
Mar 30, 1992, 10:40:44 PM3/30/92
to

A B C D E F
1 4 2 8 5 7

Ethan.

--
-------------------------------------------------------------------------
Ethan Rutter | "If I claim to be a wise man,
earu...@athena.cas.vanderbilt.edu | it surely means that I don't know."
Math Dept. | - Carry On Wayward Son, by Kansas

Tom Carmichael

unread,
Mar 31, 1992, 2:25:49 AM3/31/92
to


Answer follows...

The number is 142857

(A=1
B=4
C=2
D=8
E=5
F=7)

Tom

--
"Sleep is a poor substitute for caffine."| Tom Carmichael
- The Wizardry Compiled | tac...@hertz.njit.edu
-----------------------------------------| to...@shock.njit.edu
#include <stddisclamer.h> |

Mick Gulovsen

unread,
Apr 3, 1992, 8:51:18 AM4/3/92
to
Hi there Shere,

At last an easy one

S> ABCDEF * 2 = CDEFAB
S> ABCDEF * 3 = BCDEFA
S> ABCDEF * 4 = EFABCD
S> ABCDEF * 5 = FABCDE
S> ABCDEF * 6 = DEFABC

By reasoning A MUST be 1 to keep the result of the x 6 calc to a 6 digit No.
After that it is a simple matter to get the rest (ie x3 ends with a 1 MUST mean
F=7 etc).
Here is the result

A=1
B=4
C=2
D=8
E=5
F=7

CYA

* Origin: Andy's BBS: Melb Australia - 61-3-359-6378 (3:635/503)

Raghunath K Rao

unread,
Apr 6, 1992, 5:22:54 PM4/6/92
to

Generates the 6 digit repeating sequence of 1/7 = 0.142857142857.

---------------------------------------------------------------------
_____ ___ _______
K. RAGHUNATH RAO /____/ \ /__/\ /______/\
email : ths...@iitmax.iit.edu | __ \ /| / _ \ \ / ___ \ |
sleepy (res) : (312)791-9428 | |__) |/ / /_\ \ \ | / | \ | |
sleepier (off) : (312)567-3407 | __ /\ | ___ | | | | | | | |
| | \ \ \ | / | \ | | | | |_| | |
It is the intonation and not | | |\ \ \ | | | | | | | \/__/ |/
the intention that matters!! |_|/ \_\/ |_|/ |_|/ \______/

---------------------------------------------------------------------

Thorne Kontos

unread,
Apr 7, 1992, 5:45:59 PM4/7/92
to

Once you determine A=1, the rest of the digits fall into place
quickly...


Therefore:


The solution is:
A=1, B=4, C=2, D=8, E=5, F=7

Shankar Hemmady

unread,
Apr 7, 1992, 6:48:47 PM4/7/92
to


It is also interesting to observe that the number 142857 is the recurring
sequence that you obtain for 1/7

1/7 = 0.142857 142857 ...

Now 2/7, 3/7, 4/7, 5/7, 6/7 correspond to the recurring circular sequences which
are the same numbers in the problem.


-Shankar Hemmady


Rich Wenner

unread,
Apr 8, 1992, 12:43:20 PM4/8/92
to
In article <1992Apr6.2...@iitmax.iit.edu> ths...@iitmax.iit.edu (Raghunath K Rao) writes:
>>
>> ABCDEF * 2 = CDEFAB

Etc. (you've seen it a bazillion times by now).

>Generates the 6 digit repeating sequence of 1/7 = 0.142857142857.

Yes, this is true, and before someone else starts an eternal
thread, let me say that yes, a variation of the same trick works
with the reciprocals of 19, 29, 97, and many other numbers. I can
not find any number N whose reciprocal is a repeating decimal of N-1
digits for which the trick does not work. If someone has a proof
or disproof, I'd like to see it via email, but let's not bore
everybody else with it, OK? If you have a proof, you and I are probably
the only ones in the universe who care. ;-)


>
>---------------------------------------------------------------------
> _____ ___ _______
>K. RAGHUNATH RAO /____/ \ /__/\ /______/\
>email : ths...@iitmax.iit.edu | __ \ /| / _ \ \ / ___ \ |
>sleepy (res) : (312)791-9428 | |__) |/ / /_\ \ \ | / | \ | |
>sleepier (off) : (312)567-3407 | __ /\ | ___ | | | | | | | |
> | | \ \ \ | / | \ | | | | |_| | |
>It is the intonation and not | | |\ \ \ | | | | | | | \/__/ |/
>the intention that matters!! |_|/ \_\/ |_|/ |_|/ \______/
>
>---------------------------------------------------------------------

--
Rich Wenner --(o)--(o)-- I really hate this damn machine.
EDS/TSD/DSD/FSD/CSDPS ( /\ ) I wish that they would sell it.

\ mmmm / It never does quite what I mean,

0 new messages